Pair of interacting gear rims of the rotary machine

ABSTRACT

A pair of interacting gear rims of rotary machine has been invented as a basic structural element for engines, motors and compressors. This is the most simple and most effective design to predetermine the optimal ratio of volumes of expansion and compression processes only at the expense of the form of profile of contact surface of pair gear rims of the rotary machine. This is the ideal basic element for engines, working according to an extended indicator diagram, and for single stage compressor, working with multistage effect. 
     Applications: light and heavy vehicle engines; space power systems; heat pump systems; solar, thermal, nuclear energy systems.

BACKGROUND

1. Field of Invention

The invention concerns pair of gear rims—basic part of a design ofrotary machines, in which the working process is carried out in chambersof variable volume formed as a result of interaction of paireccentrically located gear rims, and can be used as in rotary machineswith one rotor eccentrically located in static stator, and in rotarymachines with several, in particular, with two, eccentrically locatedrotors. Declared pairs of gear rims can be used as a basic element ofengines, pumps, compressors, hydro- and pneumatic motors,turbocompressors and other types of rotary machines.

2. Description of Prior Art

Known rotary machine “Rotary Power Device”, was filed on Oct. 22, 1936by Thomas M. Gunn, patent U.S. Pat. No. 2,112,890. In this rotarymachine working chambers are created in between interacting workingsurfaces of a pair of gear rims, placed on the inner surface of theouter rotor and on the outer surface of the inner rotor. The rotors areplaced with eccentricity, the value of which equals the difference ofradiuses of interacting sections of surfaces of interacting gear rims onthe outer and inner rotors respectively.

The profile of contact surface of inner and outer gear rims has an axisof symmetry, bounded by conjugated arcs and represents the closed smoothcurve consisting of n>2 identical parts, conjugated among themselves.The identical part of contact surface of a gear rim is bounded by threeconjugated arcs of a circle.

The machine contains inlet ports placed in end caps and discharge portsthat are uniformly spaced with respect to the axis of rotation of spurwheel. Each of the discharge ports will move periodically into alignmentwith the exhaust passage opening through the circumference of theeccentric.

The existence of three conjugated arcs in identical part of the surfaceof gear rim in case of using discharge ports inside of inner rotor leadsto serious loss of the yield and productivity of the machine. It is aresult of the following feature of gear rim profiles that contains threearcs.

The chambers of variable volume are created in the area of conjugationof surfaces of different curvature. Abrupt change of the volume ofcreated chamber is taking place in this area. If the port of slide-valvemechanism is placed in this area, on condition that this mechanism isfunctioning, while the port is wholly located within the chamber, thenat the moment when the port is wholly located within the chamber, thischamber has a large volume that is totally lost for the working process,which lowers the yield and the productivity of the machine. Fordecreasing this volume it is possible to decrease the cross-section ofthe port, but it will cause an increased loss of energy, which means thedecrease of yield of the machine.

More over during the creation of chambers the surfaces are increasingthe most at the expanse of the surfaces with lower curvature. The lowerthe curvature radius of the surface of the inner rotor, the faster itopens at lower chamber volumes. In ideal case a flat surface totallyopens at minimal chamber volume (although using flat surfaces leads todrastic loss of the productivity of the machine—patent EP 0 894 979 A1).

In the gear rim, identical part of which consists of three arcs, the arcof the smallest curvature is placed on the outer part of the inner rim,outside the point of identical part of the profile, that is nearest tothe axes of the gear rim, in the optimal case (Patent WO 94/08140), itcontains this point as the endpoint. Therefore slide-valve port has asizable extraneous volume since it cannot be placed at a minimaldistance from the axes of control gear, that is coincides with the axesof the gear rim. It leads to additional lowering of the yield andproductivity of the rotary machine.

Patents similar to patent U.S. Pat. No. 2,112,890 are patents WO94/08140 (JP 405202869A), EP 0 894 979 A1, JP 355023353A, JP 406280758A,all of them contain all the above mentioned drawbacks of gear rims withidentical parts made of three conjugated arcs.

From the said above it follows, that it is impossible to create a gearrim with identical parts constructed from three conjugated arcs, thatprovide effective work of a control gear placed within the inner rotor.

SUMMARY

The invention, briefly, concerns a profile of contact surface of a gearrim of a rotor and/or stator of a rotary machine, having no less thanone pair of gear rims—inner and outer, interacting with each other withcreation of variable volume chambers, eccentrically located one insidethe other with eccentricity e equal to the difference of the interactingsurface radiuses. The claimed machine can have one pair of gear rims,interacting with each other with creation of variable volume chambers orseveral such pairs.

The profile of contact surface of inner and outer gear rim has an axisof symmetry, bounded by conjugated arcs and represents closed smoothcurve, consisting of n>2 identical parts, conjugated among themselves.Identical part of the inner gear rim is bounded by the arc of radius p₁,conjugated at its ends with the arcs of radius q₁ and of radius a+p₁,where a=p₁+q₁. Arc of radius q₁ conjugated at the other end with the arcof radius b+q₁, where length b>0. Arc of radius b+q₁ is conjugated atthe other end with the arc of radius a+p1 of adjacent identical part,which completes the gear rim profile.

Identical part of the outer gear rim is bounded by the arc of radiusp₂=p₁+e, conjugated at its ends with the arcs of radius q₂=a−p₂ and ofradius a+p₂. Arc of radius q₂ conjugated at the other end with the arcof radius b+q₂, which is conjugated at the other end with the arc ofradius a+p₂ of adjacent identical part, which completes the gear rimprofile.

From the said above it follows, that center of arcs of radius p₁ and p₂is arbitrary placed at the distance a>0 from the center of arcs ofradiuses q₁, a+p₁, q₂, a+p₂. The center of arcs of radiuses b+q₁b+q₂ isplaced at the distances b>0 and b+2a from the center of arcs of radiusesq₁, a+p₁, q₂, a+p₂ given and adjacent identical parts.

Within the inner gear rim slide-valve is placed. This slide-valvecontains spool valve and slide-valve ports, at that slide-valve portshave exit into contact surface of the inner gear rim in the part of itsprofile of the radius b+q₁.

Partition of the working surface profile into identical elements is aparticular way of describing the profile. This invention defends theform of the profile of the rotor, bounded by conjugated arcs in a givenorder independently from grouping identical elements and without it.

The invention defends the profile of contact surface of a gear rim ofthe rotary machine, which provides for the creation of two types ofchambers of variable volume. Achieving—more than a double distinctionbetween volumes of processes, carried out in the machine,—expansion andcompression, and only at the expense of the profile of contact surfaceof a gear rim. At the same time, the increase of specific productivityand yield of the rotary machine, both inner and outer gear rims arecharacterized by a uniform technique of construction; that considerablysimplifies design, and manufacturing of rotors.

The invention defends the profile of contact surface of a gear rim ofthe rotary machine, with identical parts constructed from fourconjugated arcs that provide effective work of a control gear placedwithin the inner rotor.

DRAWING FIGURES

FIG. 1. Pair of gear rims at n=7. General view.

FIG. 2. Construction of an identical part of a profile of contactsurface of pair of gear rims; generic case; n=4.

FIG. 3. Construction from identical parts of full profile of contactsurface of pair of gear rims; generic case; n=4.

FIG. 4. Working relative placement of a pair of interconnected gearrims; generic case; n=4.

FIGS. 5a-d. Disk version of rotors with two pairs of gear rims.

FIGS. 6a-b. A schematic example of possible design of the machine.

FIGS. 7a-b. A schematic example of possible design of the machine usingparts of working surface with arcs of radius b+q₁ for placing in itslide-valve ports.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1. General view of the pair of gear rims is given at n=7. Pair ofgear rim consists of an inner gear rim 1 and outer gear rim 2.

FIG. 2 illustrates identical part k, kε[1,n], of a declared profile ofcontact surface of both inner and outer gear rims of the rotary machine.

Each gear rim contact surface profile is bounded by arcs with centerpoints P_(k) arcs of radiuses p₁ and p₂, Q_(k) arcs of radiuses q₁,a+p₁, q₂, a+p₂ and S_(k) arcs of radiuses b+q₁b+q₂, kε[1,n].

The centers P_(k) are arbitrary located at distance a from centersQ_(k), that is they can be located on circles of radius a with thecenters Q_(k). The location of the centers P_(k) relative to centersQ_(k) defines a slope of rim teeth. Center S_(k) is located at adistance b>0 from the center Q_(k) and at a distance b+2a from thecenter Q_(k+1) of adjacent an identical part k+1. The concrete locationof centers S_(k) relative to centers Q_(k) defines ratio of volumes ofexpansion and compression processes, which are carried out in themachine. On FIGS. 2-4 the numbering of identical parts of a rim isaccepted in a counter-clockwise direction, that defines a direction of aslope of gear rim teeth. At change of direction of numbering ofidentical parts of a rim, the direction of teeth slope of a gear rimwill change.

Profile of an identical part k of a contact surface of inner gear rim islimited by an arc C₁ B₁ of a radius p₁ with the center P_(k), conjugatedby one end in a point C₁ with an arc C₁ D₁ of a radius q₁=a−p₁ with thecenter in Q_(k) and at the other end in a point B₁ with an arc A₁B₁ of aradius a+p₁ with the center Q_(k)

The arc C₁ D₁ is conjugated in a point D₁ with an arc D₁ E₁ of a radiusb+q₁ with the center S_(k). From a condition of limitation of a profileof contact surface by conjugated arcs of circles, follows, that adjacentasymmetrical parts of rim profile are conjugated among themselves, thatis the arc D₁ E₁, limiting an identical part k of a profile of contactsurface of an inner gear rim, in a point E₁ is conjugated to an arc A₁B₁ adjacent identical part k+1 of a profile in a point A₁. That is twocircles of radiuses b+q₁ and a+p₁ with centers in S_(k) and Q_(k+1) areconjugated and also two circles of radiuses a+p₁ and b+q₁ with centersin Q_(k) and S_(k−1) are conjugated, where Q_(k+1) and S_(k−1)—centersof arcs with radiuses a+p₁ and b+q₁ of adjacent identical part k+1 andk−1 respectively.

Since the conjugation of two arcs occurs in a point on their centerline,the distance between centers S_(k) and Q_(k+1), and also centers Q_(k)and S_(k−1) is equal (b+q₁)+(a+p₁)=b+2a.

From FIG. 2 it is clear, that part of profile limited by the arc D₁ E₁of radius b+q₁ with center S_(k) contains a conjugated part placedclosest to the axes with order of symmetry n−C_(n) and is ideally suitedfor placing in it slide-valve port.

Profile of an identical part k of a contact surface of outer gear rim islimited by an arc C₂ B₂ of a radius p₂ with the center P_(k), conjugatedby one end in a point C₂ with an arc C₂ D₂ of a radius q₂=a−p₂ with thecenter in Q_(k) and at the other end in a point B₂ with an arc A₂ B₂ ofa radius a+p₂ with the center Q_(k), concentrical to an arc C₂ D₂

The arc C₂ D₂ is conjugated in a point D₂ with an arc D₂ E₂ of a radiusb+q₂ with the center S_(k). From a condition of limitation of a profileof contact surface by conjugated arcs of circles, follows, that adjacentasymmetrical parts of rim profile are conjugated among themselves, thatis the arc D₂ E₂, limiting an identical part k of a profile of contactsurface of an outer gear rim, in a point E₂ is conjugated to an arc A₂B₂ adjacent identical part k+1 of a profile in a point A₂. That is twocircles of radiuses b+q₂ and a+p₂ with centers in S_(k) and Q_(k+1) areconjugated and also two circles of radiuses a+p₂ and b+q₂ with centersin Q_(k) and S_(k−1) are conjugated, where Q_(k+1) and S_(k−1)—centersof arcs with radiuses a+p₂ and b+q₂ of adjacent identical part k+1 andk−1 respectively. Since the conjugation of two arcs occurs in a point ontheir centerline, the distance between centers S_(k) and Q_(k+1), andalso centers Q_(k) and S_(k−1) is equal (b+q₂)+(a+p₂)=b+2a.

FIG. 3 illustrates the construction from identical parts of a contactsurface of pair of gear rims in the generic case while n=4.

Pair of profiles has an axis of symmetry of the fourth order C₄. Eachcontact surface profile of a gear rim consists of four identical parts,conjugated in their boundary points. For illustration purposes, thepoints of inner and outer rims with identical indexes are connected bysegments, dividing pairwise identical parts of a pair of gear rims. Thecenters of all arcs, that limit profiles of both inner and outer gearrims, for an identical part k are located in points P_(k), Q_(k) andS_(k) kε[1,4].

FIG. 4 illustrate a working condition of interaction of an inner rim 1and outer rim 2, which are located with relative eccentricity e=|p2−p1|=q1−q2 |. On both sides of a tooth of the gear rim two types ofvariable volume chambers are created: A and B. Simply connected region,where gear rims are not interacting, is the chamber of variable volumeC.

Chambers of the type A or B, in which expansion process takes place,after reaching it's maximal volume, they break up and unite with chamberC. Chambers of the type A or B, in which compression process takesplace, are created in their maximal volume as a result of closingportion of space of chamber C.

The maximal values of volumes vary. The ratio of this variance, for aconcrete working process, is set at the design stage of the machine. So,the maximal volume of chambers of type A and B, on FIG. 4 have a ratioof distinction 2.65.

On FIG. 4 it is evidently visible, that the maximal volume of thechamber of type A surpasses the maximal volume of the chamber of type Bwhich provides increase of yield of the machine or specific capacity,depending on a concrete working process.

After setting macro parameters e, a, b and interposition of centersP_(k), Q_(k) and S_(k) the volume of chambers is singularly defined as afunction of rotation angle of the rotors and does not depend onredistribution of values of radiuses p1, p2, q1, q2. It means that whenmacro parameters are set, thermodynamics, technical and volumecharacteristics of the machine become full invariants relative to thetask of its macro parameters.

FIGS. 5, a-d. Rotors of disk version, as an illustration of use in therotary machine more than one pair of gear rims.

The rotors (7 and 8) contain two pairs of gear rims. The rotor (7)mounted on the shaft (11), contains an inner gear rim (3) of internalpair and outer rim (6) of external pair of gear rims, mounted on the hubplate (9). The rotor (8) mounted on the shaft (12), contains combined bythe non-working surfaces an outer rim (4) of internal pair of gear rimsand inner rim (5) of external pair of gear rims, mounted on the hubplate (10). The gear rims (4 and 5) can be executed as one whole. Therotors (7 and 8) are mounted on shafts (11 and 12) with eccentricity e.

Characteristic length a can differ for different pairs of gear rims. Twopairs of gear rims on rotors of disk version can, for example, be usedboth as the twostage compressor, and as the turbocompressor engine. Incase of the twostage compressor external pair of gear rims (5 and 6) isused as the first stage of the compressor, while an internal pair ofgear rims (3 and 4)—as the second stage of the compressor. In case ofthe turbocompressor engine internal pair of gear rims (3 and 4) is usedas compressor, and outer pair of gear rims (5 and 6) is used asturbine—expander.

FIGS. 6a-b. An example of use of the invention in the machine used asthe engine of external combustion, working on the extended indicatordiagram, or as the single step compressor with an effect of a multistagecompressor.

FIG. 6a schematically illustrates machine containing a case (13) inwhich the outer rotor (15) with coaxial gear rim (17) is mounted.Profile of a contact surface of gear rim (17) consists from n identicalparts described on FIG. 2.

Inside a rotor (15), with eccentricity e the inner rotor (14) withcoaxial gear rim (16) is mounted. Profile of a contact surface of gearrim (16) consists of n identical parts described on FIG. 2.

The rotors are designed and mounted one relative the other according toFIGS. 3,4. The rotors are mounted with a possibility of synchronizedrotation in one direction with identical speed. At rotation of rotorsthe contact surfaces of gear rims interacting among themselves, in sucha way that the operating space within a pair of interacting gear rims issplit in the area of interaction of gear rims into closed chambers ofvariable volume of two types—type A and type B. Area of operating spaceinside a pair of gear rims, in which the operating surfaces of rims donot interact, is a chamber of variable volume of the third type C.

In a process of mutual displacement of the patches of interactingsurfaces of gear rims, chambers type A and type B change in opposite wayand stop their existence with the termination of interaction of thepatches of interacting surfaces of gear rims.

The opposite change of volume of chambers type A and type B means, thatat the moment of a beginning of interaction of patches, of interactingsurfaces of gear rims, closing chambers, one of chambers, for example,type A, has it's possible maximal volume, and the chamber, type B, hasit's possible minimal volume. During rotation of gear rims occursdisplacement of lines of interaction of their working surfaces and, asresult, redistribution of volumes between chambers A, B and C. Thus isvolume of the chamber type A, formed with initial maximal volume,continuously decreases to the minimal volume at which chamberdisappears, while volume of the chamber type B, formed with initialminimal volume is continuously increases up to the maximal volume atwhich occurs its opening and merging with chamber C. As simultaneouslythere is an interaction of several pairs of teeth of gear rims, severalprocesses are simultaneously carried out that are distinguished only byphases.

Chamber C is simply connected region of space and working medium canfreely flow into any part of this region. Particular feature of claimedpair of gear rims is the opportunity of the task of a required ratiobetween the maximal volumes of chambers of type A and of type B, in theprocess of designing the rotary machine.

In the case of the machine there are four channels (18,19,20,21),connecting chambers of the machine by means of designated connectingdevices, marked by the same numbers (18,19,20,21), with entrance andexit feeds and/or by devices with the possibility of capping unusedchannels.

The connecting device (18) connects through the channel (18) externalfeeds with region of chamber C, in which there is a creation of chamberstype B in their greatest volume.

The connecting device (19) connects through the channel (19) externalfeeds with region of chamber C, in which there is an opening of chamberstype A in their greatest volume, and their merging with chamber C.

The connecting device (20) connects through the channel (20) externalfeeds to chambers of type B.

The connecting device (21) connects through the channel (21) externalfeeds to chambers of type A.

For the machine to function as the external combustion engine, thechannel (20) through the connecting device (20) is connected with aninput device, and the channel (21) through the connecting device (21) isconnected with the output device of the combustion chamber (22),containing also a channel for fuel injection (23).

Design of the combustion chamber (22), the communications of channels(18,19,20,21) with chambers of variable volume and with interchamberspace are carried out by various known ways and thereof are markedschematically. Through the channel (18) takes place the purge by freshair of the chamber type B at the phase of its formation (at this phaseits volume is maximal). The purge by fresh air of chambers type B stopsafter their formation. At the further rotation of rotors of the machine,after achieving a certain degree of compression, compressed air fromchambers type B through channel (20) is fed into the combustion chamber(22), where it is mixed with injected through the channel (23) fuel andwhere combustion accurse.

The turned out working medium through the channel (21) is fed intochambers type A at the initial phases of their expansion. At the certainphase of expansion of chambers type A, the feed of a working medium intothem stops, and the further expansion occurs only at the expense ofinternal energy of a working medium. After achievement by chambers typeA of maximal volume, they are disconnected, merging with the chamber C,then the exhausted working medium through channel (19) is directed to anexit feed.

As volume of chambers type A is grater than volume of chambers type B,the extraction of energy of a working medium in the considered scheme onvalue ΔP×ΔV (ΔV−difference of volumes of chambers type A and B,ΔP−average pressure on phases of expansion in oversize volume ofchambers type A) is grater, than in known machines with equal volumes ofcompression and expansion.

The machine can function as the multistage compressor. For this purposechannels (18) and (19) capped, the channel (21) is switched by means ofa connecting device (21) with an input feed, and the channel (20) isswitched by means of the connecting device (20) with a output feed. Theeffect of a multistage compression is possible because through thechannel (21) occurs sucking in of gas into chambers type A, after whichbreak the gas gets into chamber C, carrying out a role of a receiver.From the chamber C gas through chambers type B, formed by closing ofpartial volume of the chamber C, is displaced through the channel (20)into an output feed. Since volume of chambers type A is grater thanvolume of chambers type B, therefor the volume of gas entering intochamber C through chamber type A is grater than the volume of gasexiting through chambers type B. It results in increase up to anequilibrium condition of pressure in the chamber C, that is chamber Cacts as a preliminary stage of compressor.

FIGS. 7a-b. A schematic example of possible design of the machine usingparts of working surface with arcs of radius b+q₁ for placing in itslide-valve ports.

On FIGS. 7a-b there is a schematic representation of machine withoutcasing that contains a base (24) with fastening openings (25) on whichthe base element (26) is rigidly fixed. Base element 26 is intended forplacing of inner rotor (14), shaft (27) of outer rotor (15), slide-valvecontrol gear that contains spool valve (28) placed on shaft (29) withthe possibility of adjustment by means of handle (30). Base element (26)also contains a channel (31) that is connecting inlet or outlet pathway(not shown) with slide-valve control gear by means of branch pipe (32).Inner rotor (14) placed concentrically on base element (26) with thepossibility of free rotation. Inner rotor (14) in the zone ofslide-valve control gear has a ring shaped hollow (34) in which spoolvalve (28) is placed, and restricting lobe (35) of base element (26)that ensures isolation of the area where the working process is takingplace (chambers type A) from adjacent areas (chambers type C) within themachine. Within the inner rotor (14) slide-valve ports (33) are placed,they have a depth of the ring hollow (34) and an exit into the externalcylindrical surface of the rotor in the zone of working surface of theradius b+q₁. The section of these ports is very large, while the volumethey require is so small, that it does not have any negative effect onthe working process taking place in the machine. Outer rotor (15)concentrically fixed on the end cap (36), placed on the shaft f themachine (27). The function of the second end cap is performed by thebase (24). Outer rotor (15) contains channels (37) for neutralizationadjustment of volume of chambers type B unused in the working process.These channels (37) are also used for removing the used working mediawhen the machine is working as a motor, and used for input of workingmedia when the machine is working as a compressor.

The machine works as a compressor in the following way. Shaft (27)revolves anticlockwise from the external energy source. Together withthe shaft outer rotor (15) is also rotating, as a result of theinteraction of gear rims the inner rotor (14) is synchronically rotatingtoo. As result of interaction of gear rims of rotors (14) and (15)chambers of variable volume are created. At that chambers of type A arecreated with maximal volume with following decrease of the volume tozero during the changing phases of rotation. For the maximal values ofchambers volumes ports (33) in the cylindrical surface of the innerrotor (14) are closed by spool valve 28. After rotating at an angle,defined by the placement of spool valve (28), ports (33) open andcompressed gas, the pressure of which is defined by placement of spoolvalve (28), is channeled through channel (31) into the exit outlet (notshown) of the machine. Compression ratio is adjusted by means ofrotating spool valve (28) with handle (30).

The machine works as a motor in the following way. Compressed gas froman inlet channel (not shown) connected to the branch pipe (32) issupplied into channel (31), from where through ports (33) (in thecylindrical surface of the inner rotor (14)) it fills at a constantpressure chambers of type A, at phases where the volume of chambersvaries from zero to the value defined by the position of the spool valve(28). Under the influence of pressure on rotor system pressure forcesare applied in such a way that the rotors are revolving clockwise. Afterchamber A passes the phase where it is connected with channel (31)through port (33) within the cylindrical surface of inner rotor 14, thesupply of pressured gas is terminated and the following expansion istaking place under the influence of inner forces. Changing the placementof spool valve (28), by means of shifting handle (30), it is possible toadjust power settings from maximal yield to maximal power.

Although the invention has been described and illustrated with a certaindegree of particularity, it is understood that the present disclosurehas been made only by way of example, and that numerous changes in thecombination and arrangement of parts can be resorted to by those skilledin the art without departing from the spirit and scope of the invention,as hereinafter claimed.

I claim:
 1. Pair of interacting gear rims of the rotary machineincluding no less than one said pair of gear rims interacting with eachother with creation of variable volume chambers, eccentrically locatedone inside the other with eccentricity e equal to the difference of theinteracting surface radiuses; profile of contact surface of inner andouter gear rim has an axis of symmetry, bounded by conjugated arcs, andconsisting of n>2 identical parts, conjugated among themselves; saididentical part of the said inner gear rim is bounded by the arc ofradius p₁, conjugated at its ends with the arcs of radius q₁ and ofradius a+p₁, where a=p₁+q₁, said arc of radius q₁ conjugated at theother end with the arc of radius b+q₁, where b>0, which is conjugated atthe other end with the said arc of radius a+p₁ of adjacent identicalpart, which completes the said gear rim profile; said identical part ofthe said outer gear rim is bounded by the arc of radius p₂=p₁+e,conjugated at its ends with the arcs of radius q₂=a−p₂ and of radiusa+p₂, said arc of radius q₂ conjugated at the other end with the arc ofradius b+q₂, which is conjugated at the other end with the said arc ofradius a+p₂ of adjacent identical part, which completes the said gearrim profile.